1. The Field of the Invention
The present invention is related to identification of individuals, and fluids and tissues obtained from individuals, through analysis of the antibodies carried by such individuals. More specifically, the present invention is related to the identification of individuals by analysis of the antibody profile of such individual. The present invention is further related to distinguishing one individual from another individual by comparing the antibody profiles of said individuals.
2. Technical Background
In various contexts it is very important to identify individuals with a high degree of accuracy. It is also important to have the capability to differentiate individuals, one from another. Furthermore, it is also important for some purposes to link tissue, body fluid, or other biological samples with the individual producing such samples.
The need for such identification methods may arise in any one of a wide variety of situations. For example, the need for accurate means of identification is obviously necessary in law enforcement. It may be critical in the investigation of a crime to link tissue, blood, semen, or the like, left at a crime scene with the owner of such biological material. If such material can be linked to a specific individual, law enforcement authorities will be aided immeasurably in solving the crime and apprehending and convicting the criminal.
Similarly, identification of individuals is important in determining paternity or maternity. Determination of parenthood arises in a number of contexts. For example, it may be important to identify mothers and newborns in the hospital setting in order to match the appropriate newborn with the appropriate mother. It may also be important to determine parenthood for purposes of immigration and naturalization. Many countries grant favorable immigration status to immediate family members of citizens. However, establishing a familial relationship may be difficult in some cases. In addition, the subject government has a related interest in preventing immigration fraud.
Various screening techniques are presently employed in order to determine parenthood. These include blood typing and comparing other physical characteristics. As will be discussed in more detail below, it is now possible to do some paternity screening by analyzing the DNA of the individuals involved. Each of the techniques used in the past, however, has serious limitations.
Another situation which calls for the matching of tissue or biological fluid samples with an individual is in the area of biological testing. Many types of biological tests are presently employed. These include urine tests, blood tests, and tests on tissue samples for cancer and other diseases.
In the context of such tests, there is a corresponding need to assure that the proper sample is attributed to the appropriate individual. If, for example, an individual is a drug user, it will clearly be to that individual's benefit not to be tied to a drug containing urine or blood sample. Examples of where this type of situation could arise include drug testing of athletes, drug testing of race horses, and employee drug testing of the type now carried on by numerous employers. In these contexts individuals have attempted to alter results, switch samples, or otherwise attempt to defeat the effectiveness of the test. If samples could be precisely matched to the individual, these problems could be minimized.
Similarly, it is important that samples used for diagnosis of disease be correlated to the donating individual in order to provide an accurate diagnosis. Again there are documented cases of samples being inadvertently switched, resulting in difficulty in providing accurate diagnosis of disease.
Other situations where if may be important to match, or even separate, biological materials would be in the context of a disaster or war zone where it is desirable to match body parts. In this type of context it may be difficult or impossible, using known techniques, to separate or match body parts with any degree of accuracy.
In order to accomplish sorting of biological samples, identification of individuals, and other related tests, various techniques are now used. The three most common non-visual means for identifying people include blood typing, fingerprinting, and voice exemplars. Other methods include retinal scans and dental x-rays.
Blood typing is based on the existence of groups of antigens present on blood cells. For example, the ABO system refers to four different groups of blood cell antigens: A, B, AB, and O. The letters designate antigens present on the surface of the red blood cells. Type A individuals have the A antigen; Type B individuals have the B antigen; Type AB individuals have both antigens; and Type O individuals have neither the A nor the B antigen.
By analyzing a sample of a person's blood it is possible to identify that individual to a particular blood group. It is, of course, immediately apparent that while this method may be used to identify an individual out of a small group of individuals, the method is limited when identification of an individual out of thousands is the goal. To do this, testing for many more blood group antigens is required and each test is a separate assay. Some newer tests make use of different isozymes that are present in body fluids, yet these tests also suffer from the same limitation as do the blood typing tests. These methods can exclude certain individuals, but they cannot typically differentiate among a large number of individuals, or between members of the same blood group.
Fingerprinting is perhaps a more accurate way of identifying an individual, and is widely used by virtually all law enforcement agencies around the world. It is based on the appearance of characteristic patterns of an individual's fingers, such as swirls, valleys and ridges. When this method is used, a statistical evaluation is given as to the degree of correspondence between known fingerprints obtained from the individual, and those fingerprints which are sought to be matched to the individual. The procedure is technically arduous, and often not definitive. For example, the way that fingerprints are catalogued allows room for ambiguities. Furthermore, in many instances of crime, fingerprints are not available.
The third procedure for identifying individuals is to match a voice recording with a voice exemplar of the individual. It is, of course, apparent that this method has little value in most instances, as there is seldom access to a recording of an individual's voice prior to the time that the match is sought.
A variety of immunological/biochemical tests based on genetics, are routinely employed in paternity testing, as well as for determining the compatibility of donors and recipients involved in transplant or transfusion procedures, and also sometimes as an aid in the identification of human and animals. Generally, the existing procedures involve serological testing for proteins encoded by the Human Leukocyte Antigen gene loci or, as it is more commonly known, HLA complex.
Although a good deal of information is known concerning the genetic makeup of the HLA locus, there are many drawbacks using HLA serological typing as the means for identifying individuals in a large group. This is primarily because of the complexity of the serum used to do the testing, and the lack of widespread availability of standard serum necessary to conduct the test, especially when dealing with species other than mouse or man. Each of the HLA antigens must be tested for in a separate assay, and many such antigens must be identified in order to identify one individual, an arduous process when trying to identify one individual in a large group.
In addition to serological and mixed lymphocyte testing for the products of the HLA loci, more recent studies have identified DNA restriction fragment length polymorphisms (RFLP'S) indicative of different individuals, and these have been used in paternity testing, and transplant and transfusion compatibility testing. Other workers have developed identification systems based on the analysis of repetitive DNA sequences (called "hypervariable minisatellite" regions or "variable number tandem repeats" in human DNA. This method can also be applied to animals. The systems that are based on DNA RFLP, or DNA "hypervariable minisatellite" regions, however, do not discriminate between genetically identical animals such as twins, and depend on the particular DNA probe used to discriminate between individuals that are closely related.
It will be appreciated that while the above methods are useful for identifying individuals, performing paternity tests, and for transplant and transfusion compatibility testing, these methods are presently technically arduous when used for the purpose of identifying individuals. DNA and related testing methods are also time-consuming and often necessitate the use of expensive laboratory equipment.
Accordingly, it would be a significant advancement in the art to provide a single test for determining identity, separating individuals, and for determining the source of biological fluids and tissues. It would be further advancement in the art if such a test could be provided which was sufficiently powerful to identify individuals with a very high degree of certainty. It would also be a significant advancement in the art to provide such a test which was much more simple to use than many known tests (such those employing DNA analysis). It would be a further advancement in the art to provide kits for use and employment of such a test method.
Such methods and apparatus are disclosed and claimed herein.